This invention pertains to the reforming of liquid, gaseous or vaporized hydrocarbons, inorganic compounds, or mixtures thereof, to produce hydrogen for direct use or for use in a fuel cell. More particularly, it pertains to a thermoelectric reformer unit for dissociating fossil-based hydrocarbons (e.g., methane, methanol, ethanol, gasoline, diesel oil, propane), renewable hydrocarbons (e.g., vegetable oils, or biomass oils), or inorganic compounds (e.g., water, ammonia, and hydrogen sulfide) to produce hydrogen in a thermoelectric reactor using thermoelectric technology with thermoelectric materials, including—bimetals to achieve very high conversion efficiencies.
Hydrogen has long been recognized as an ideal fuel for power generation systems with virtually no emissions of air pollutants and greenhouse gases. It can be used in fuel cells or hydrogen-fueled internal combustion engines to power vehicles or to provide electricity and thermal energy (cogeneration) in stationary, distributed energy generation units. Fuel cells are being developed for applications in the transportation sector and the distributed power generation sector because the expected energy security, environmental, and economic benefits are truly significant. Efficient reformer for producing hydrogen for use in fuel cells is an active area of invention. For example, Takahashi in U.S. Pat. No. 5,746,985 and Edlund, et al in U.S. Pat. No. 6,221,117 teach use of a steam reforming reaction, Krumpelts, et al in U.S. Pat. No. 5,929,286, Admed, et al in U.S. Pat. No. 5,939,025 and U.S. Pat. No. 5,942,346 teach the use of partial oxidation processes, Wang in U.S. Pat. Nos. 7,442,364, 7,070,634, 6,458,478, 5,614,156 and 5,602,297 teach the use of thermal plasma reforming processes.
Fuel cells would be commercially viable tomorrow if there were an inexpensive, easier way to produce, transport, and distribute hydrogen. However, without widespread use of fuel cell vehicles, massive investments in a hydrogen-refueling infrastructure, such as hydrogen refueling stations are not likely to occur. Therefore, to facilitate the market acceptance and penetration of fuel cell powered vehicles, implementation of an alternative method of refueling is imperative. This commonly accepted notion is supported by the U.S. Department of Energy in its emphasis on the development of fuel-flexible multi-fueled reformers, especially for use with renewable energy sources such as bio-fuels. The present invention has high conversion efficiencies and low power consumption as a percentage of fuel cell output. Its hydrogen reformer potentially can significantly reduce hydrogen production costs to help make widespread use of fuel cell powered vehicles and stationary installations a reality.
Widespread deployment of fuel-cell-powered power plants in the United States could result in economic benefits resulting from energy saving in the range of billions of US dollars, reliable power supply, and emission reductions. Besides, fuel cell powered vehicles fueled by hydrogen derived from domestically produced alternative fuels such as ethanol, methanol, or natural gas with a reformer would simultaneously reduce the nation petroleum demand. Also, hydrogen has the potential to be a more versatile energy carrier than electricity, yielding tremendous business opportunities. Thermoelectric reformers have other applications than producing hydrogen. They can be used to destroy volatile organic compounds as taught by Wang in U.S. Pat. No. 5,614,156 or to dissociate hydrogen sulfide into hydrogen and sulfur as taught by Wang in U.S. Pat. No. 5,843,395.